[FieldTrip] Defining cfg.neighbourdist at source level

[Pomper, Ulrich]

Dear Jörn,
Thanks for you reply. I did mean source-level, so like you said, I am trying to define the neighbouring voxels for each voxel.
As far as I understand, leaving cfg.neighbours blank means that the clustering is done over the time and frequency dimensions only, not over space.
The FT help reads:
%If you specify an empty neighbourhood structure, clustering will only be done in frequency and time (if available) and not over neighbouring channels.

Has anybody done clustering in source space using all three dimensions and could explain how this works?
Cheers,
Ulrich




On 30.01.2012 16:37, "Jörn M. Horschig" wrote:
Dear Ulrich,

I think you are confusing some things there. cfg.neighbourdist is a setting for defining neighbouring sensors, thus it's not applicable for source level statistics (see ft_prepare_neighbours). However, I never did cluster-based permutation test on source-level in FieldTrip, but for me it seems that it just works by taking neighbouring voxels as neighbours. So, you shouldn't need to define anything special for running sourcelevel stats (if I am wrong, someone with more experience should correct me here).
But, maybe you meant to write sensor level, but wrote source level - in that case I'd be happy to help.

Best,
Jörn

On 1/27/2012 4:34 PM, Pomper, Ulrich wrote:
Dear list members,
I am trying to perform a cluster based permutation test on power values at source level.
I managed to run the test using just the time and frequency dimensions (cfg.neighbourdist = [])
but I am struggling with the issue of how to define the neighbourdist parameter.
I've looked through the tutorial, the FT site as well as through the mailinglist but couldn't find an answer, so I'd really appreciate any hint on this.

Thanks a lot,
Ulrich





_______________________________________________
fieldtrip mailing list
fieldtrip at donders.ru.nl<mailto:fieldtrip at donders.ru.nl>
http://mailman.science.ru.nl/mailman/listinfo/fieldtrip



--
Jörn M. Horschig
PhD Student
Donders Institute for Brain, Cognition and Behaviour
Centre for Cognitive Neuroimaging
Radboud University Nijmegen
Neuronal Oscillations Group

P.O. Box 9101
NL-6500 HB Nijmegen
The Netherlands

Contact:
E-Mail: jm.horschig at donders.ru.nl<mailto:jm.horschig at donders.ru.nl>
Tel:    +31-(0)24-36-68493
Web: http://www.ru.nl/donders

Visiting address:
Trigon, room 2.30
Kapittelweg 29
NL-6525 EN Nijmegen
The Netherlands

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20120130/c59bb28e/attachment-0002.html>